Intracytoplasmic uncoated capsids of human cytomegalovirus.

It has been generally accepted that capsids found in the cytoplasm of infected fibroblasts by adapted strain human cytomegalovirus (CMV) have bristle-like surface coating on them. This coating was said to be one of the important differences of CMV from herpes simplex virus. As well known, capsids of CMV increased in their over-all diameter through the process of moving from the nucleus to the cytoplasm. In some instances, however, uncoated capsids were detected in the cytoplasmic portions especially in the vicinity of tubular structures in the cytoplasm. It seemed that these uncoated capsids might be formed in the cytoplasm but had not emigrated from the nucleus.